1. Field
The following description relates to an optical imaging system of which a focal length may be adjusted.
2. Description of Related Art
In a needle case type optical imaging system, in which a plurality of lenses are disposed linearly or in a row, as a number of lenses is increased, an overall length of the optical imaging system is increased. For example, it is more difficult to miniaturize an optical imaging system including five lenses than to miniaturize an optical imaging system including three lenses. For this reason, there is a limitation in mounting needle case type optical imaging systems in small portable terminals.
Conversely, in a curved optical imaging system, only some lenses are disposed in a row. Therefore, curved optical imaging systems may be mounted in tight spaces. However, because the curved optical imaging system uses a plurality of refracting prisms, manufacturing costs of the optical imaging system are high, and optical performance of the optical imaging system may be deteriorated.